Three-dimensional (3D) printing is an additive printing process used to make three-dimensional solid objects from a digital model. 3D printing techniques are considered additive processes because they involve the application of successive layers of material to make the object being printed.
3D printing technology is applied in various industries for manufacturing and planning. For example, the automotive, aerospace and consumer goods industries use 3D printing to create prototypes of parts and products 3D printing has also been used in the architectural industry for printing structural models. The applications of 3D printing in private and government defense have grown rapidly as well.
3D printing has had a significant impact in the medical field. Medical applications of 3D printing have been used to produce dental implants and prosthetics. 3D printing has also been used in the fabrication of drug delivery devices. A variety of drug delivery devices may be created which allow for customizable drug release profiles.
Traditional 3D printing allows an object to be created by depositing a material over a flat fabrication platform one layer at a time. Once a first layer is deposited, a second layer is deposited on top of the first layer. The process is repeated as necessary to create a multi-layered solid object. However, 3D printing does not allow for continuous extrusion to create an object.
Bone defects may be caused by a number of different factors, including but not limited to trauma, pathological disease or surgical intervention. Because bone provides both stability and protection to an organism, these defects can be problematic. In order to address these defects, compositions that contain both natural and synthetic materials have been developed. These compositions may, depending upon the materials contained within them, be used to repair tissues and to impart desirable biological and/or mechanical properties to the bone defect.
Among the known bone repair materials and bone void fillers is autologous cancellous bone. This type of bone has the advantage of being both osteoinductive and non-immunogenic. Unfortunately, this type of bone is not available under all circumstances. Moreover, donor site morbidity and trauma add to the limitations of autologous cancellous bone. One alternative to autologous bone is allograft bone. Unfortunately, allograft bone has a lower osteogenic capacity than autograft bone, has a high resorption rate, creates less revascularization at the bone defect site, typically induces a greater immunogenic response and may result in the transfer of certain diseases.
In order to avoid the issues that attach to the use of autologous and allograft bone, one may use synthetic materials. However, known synthetic materials suffer from one or more of the following drawbacks, including unacceptable workability, handling and setting parameters, insufficient density; undesirable absorption rates; and an inability to impart adequate stability.
Generally, bone tissue regeneration is achieved by filling a bone repair site with a bone graft. Over time, the bone graft is incorporated by the host and new bone remodels the bone graft. In order to administer the bone graft, it is common to use a monolithic bone graft or to form an osteoimplant comprising particulated bone in a carrier. The carrier is thus chosen to be biocompatible, to be resorbable, and to have release characteristics such that the bone graft is accessible. Ordinarily, the formed implant, whether monolithic or particulated and in a carrier, is substantially solid at the time of implantation and thus does not conform to the implant site. Further, the implant is substantially complete at the time of implantation and thus provides little ability for customization, for example, by the addition of autograft.
Traditional methods of 3D printing do not allow for a printed mesh implant having one or more compartments to be filled with bone material and then after filling the one or more compartments with bone material, a cover is printed on the mesh implant. Thus, there is a need for a computer implemented method of producing a mesh implant having a hollow compartment, which can be filled with bone material for delivery at an intended bone repair site. There is also need for a computer system that can be used to implement the steps required to produce the mesh implant having a compartment that can be filled with bone material.